Guardian Project: SMS Encryption (non-)Options for Android

My first post was titled “Guardian Approved” as I did want to highlight applications that were of a certain quality or caliber. Unfortunately, in the realm of secure, private, encrypted short messaging (SMS), I can’t really say I have anything to approve! The best, most trusted solution out there (from CryptoSMS.org) hasn’t been ported to Android yet, and the rest of the offerings either cost too much, aren’t targeted directly at SMS, are closed source or generally poorly written alpha quality applications.

I’ve quickly realized that a quality SMS encryption application for Android (along with interoperability with other mobile phone platforms) is a critical application for the Guardian Project to focus on. One of the really cool aspects of building apps for Android is that you can completely replace the core applications on the device, meaning that an encryption-enabled SMS application isn’t relegated to a third-party status within the device. It can actual take over and replace the built in “Messaging” application and seamlessly handle SMS traffic and transparently handling encryption of messages to and from those addresses you have done a key exchange with.

Where Its At

In the meantime, here is a quick breakdown of what is available on Android today:


  • While not used for encryption, ChompSMS represents an excellent example of a “power-up” replacement for the built-in Android messaging application. It does offer an ability to send SMS through their Internet-based SMSC gateway. This means that as long as you have an mobile Internet data connection, you can send SMS messages without being monitored by the local mobile carrier, and even send SMS over a WIFI connection.

  • Encrypted SMS – $1.99 – “Parents Spy Much? Here’s your solution!” – This app is clearly targeted at the “passing secret notes in class” audience and not meant for anything serious. The encryption used seems to be of the basic letter substitution pig-latin variety, which could be cracked in about two seconds by someone with a pencil and paper.
  • Platinum RSA SMS – Free – “Encrypted text messaging service for your Android device. 1024 bit RSA math” – While the potential for this app seems good and the heavy use of the phrase “RSA math” indicates they know SOMETHING about encryption, the user interface is very confusing, even for me a seasoned user of terrible mobile user interfaces.
  • TXTCrypt – $9.99!

    “With TXTcrypt just enter your message and a password for it , now the encrypted message can only be decoded with that password , just tell it to someone , and send them message encrypted with it , they can use TXTcrypt to decode it..”. This application is very powerful and well written. However, it costs way too much for what it offers. No key change, no proper integration with SMS… it is just a basic password-based plain text encryption tool.



CryptoSMS

As mentioned before, there is a quality, open-source solution available called
CryptoSMS. From their site: “Cryptosms provides public/private key encryption, key generation and key management. it sends and receives encrypted sms and public keys, de- and encrypts files, offers key verification via fingerprints and provides a secure login. ”

Unfortunately, CryptoSMS is only available for J2ME-based phones today, which Android is not. There is a J2ME emulation app for Android, but it is a terrible user experience. What this is all adding up to is that the Guardian Project must/will plan to contribute to and otherwise support porting efforts of CryptoSMS to Android… while the user experience and integration with Android OS concepts like intents and content providers will take some work, the core engine of CryptoSMS appears to be just what is needed.

If you are in the New York area, and would like to learn more about CryptoSMS, you can attend a workshop this Thursday evening, August 13th, at The Change in Williamsburg, Brooklyn. More information available here…

Guardian-approved: Walkie-Talkie App for Android

As part of rolling out the first-phase of The Guardian Project, I will be writing short reviews of existing applications for Android-based mobile phones that share our general goals or desired functionality. The goal of Guardian, in short, is to enable safe and secure communication for activists, organizers and advocates working for good around the world through the mobile phones they carry in their pockets.

The Guardian project has no official relationship with these apps or their creators, but as we work towards developing our own unique software, we want to make sure to shine the spotlight on existing efforts that we admire and which are currently available. We’d also happily collaborate with any of them (or *you* if you are a developer reading this), and have them join our open-source efforts.

The first application is Walkie Talkie Push to Talk, which is a great alternative take on real-time VOIP or standard phone calls. Physical walkie talkie radios and Nextel-style PTT services have long been a valuable tool for many activists, and this application bring that capability to a global scale. Walkie Talkie can be used over GRPS, EDGE, 3G or Wifi networks, as well – whatever is available at the time.

Here’s a short description from the developer:

Walkie Talkie Push to Talk is a mobile application that allows walkie talkie style voice communications. Simply hold down the “Record & Send” button and speak. Messages can be sent to a group of people. Received messages are automatically played. If program is running, incoming messages arrive as soon as 15 seconds. If program is not visible, it polls in the background every 1 minute (to save battery).

The back-end messaging system used by this application is actual POP or IMAP, in other words email! If you utilize a secure IMAP/S connection with the application, then the voice communications are transmitted securely over the wireless network and Internet. If you use a service like Gmail (which offers secure IMAP access), then your access is hidden within the millions of other users accessing Gmail, as well.

Not drawing attention to your network traffic is often as important as securing your data. Also, while Gmail isn’t always the ideal service to use if you wish to retain full control of your data, it is much more difficult for an authority to block than a single proxy or a private server.

A few screenshots below:

Learn more about Walkie Talkie and download it from the Android Market today.